If you are overweight, then a common cause of numbness
in the thigh is pinching of one branch of the nerve that supplies sensation to the top of your thigh. This can occur because the weight of the abdominal fat can press on the nerve as it runs down the thigh. The treatment for this obviously is mostly weight loss
Additionally if you have a history of lower back injuries or have recently injured your back, then it is possible that a pinched nerve in your back was responsible. Usually this numbness and tingling is more down the back of the leg, but it can come around to the thigh at times. It is usually also associated with pain and spasm in the back.
I would also wonder about any sores, blisters, or red areas that might have showed up on the skin near where the strange sensations were felt. Shingles can reactivate on any part of the body, and it is possible to have a shingles outbreak on the skin over the thigh.
If the symptoms come back or if they worsen, I would definitely suggest making a visit to your primary care doctor
to see if additional workup is needed.